6alpha, 16alpha-dimethylpregnenes and intermediates



United tates vPatent O 3,030,360 6a,16a-DIl\mTI-IYLPREGNENES AND INTERlt/EDIA'IES Frank H. Lincoln and Wiliiam P. Schneider, Kalamazoo Township,'Kalamazoo County, and George B.Sp'ero, Kalamazoo, Mich., 'assignors to The Upohn Company, Kalamazoo, Mich., a corporation of Delaware No Drawing, Filed Oct. 30, 1959, Ser. No."849,707

` Y`9, Claims. (Cl. 2604239.55)

This invention relates to 60/16a-dimethyl-l7a,2ldi hydroiiyipregnene,2O4dione, ogl'a-dirnethyl-lh-,Zl dihydrOXy-'l ,4-pregi1adiene-3,20-diene, esters thereof, interrnediatesv inthe production thereof and a process for the production thereof. "7 c' v According to this' invention, 6t,l6adimethyll 7a,2vl dihydroxy-l-pregnene-S,ZO-dione and "esters thereof are prepared by epoxidizing 3-hydroxy-6,lowdimethylS- pregnen-ZO-one to produce the 'corresponding `Snaepoxide, converting the side chain' tothe A'17(20)21oic acid lower-alkyl ester A"sideuchain by the steps of glyoxalating, dibrominating, and reaction with an alkalimetal lower-alkoxide a loWer-alkanol, reducingthe resulting compound with lithium aluminum hydride to producek 3,5a,2l-trihydroxy 6ot,l6c. -1dimethyl-l7(20) pregnene, selectively esterifying them-hydroxy group to produce a'2l-acyloxy group, yoxidizing the 3-hydr`oxy group to 'a '3-keto group, oxidativcly hydroxylating the ,dllfkdouble bond to produce a l7a-hydroxy-20-keto group, and then" dehydrating the 5oz-hydroxy' group to `produce '6zx,l6a dimethyl-171mll-dihydrOXy-ipregnene- 3,20-dione'2l-acylate. Reaction of this compound with seleniumy dioxide 'produces 6a,l6adimethyll7,2ldihydroXy-l,4'-pregnadiene 3,20 dione 21 acylatefHydrolysis ofthe Zl-acylatev group of these-two compounds produces' 611,16a-dimethyll7u,2l-dihydroxy-4-pregnenel3",20dione and Gordon-dimethyl l7a,2l -dihydroxy-IA- pregnadiene3,20dione, respectively. """elaL-di ethyl 1'7c.,2l dihydroXy-4-pregnene-3,20- dione, 60:,16 dimethyl l7oc,2l `-v-dihydroXy-l,1l-pregnadiene-3,20dione, and the 2l-esters`thereof possess pharmacological activity, yincluding glucocorticoid, anti-inflammatory and progestational activity with a minimal amount of associated 'mineralocorticoid activity. They can be administered inthe same manner as hydrocortisone and its: esters. :They are also useful inthe production' of the 'corresponding ll-oxygenatedcompoundsk which also vhave anti-inflammatory and glucocorticoid activity, e.g.,' vby hydroxylating with an llhydroxylating species of a fungi, e.g., Czmrtinghamella Lbltc'esleeana, Trchtltecium rs'en'i, Czirvularz'a'lunuttz, vO mp'hl' 'iralucz'dm etc'.,"to produce 6a,l6a dimethyl-lll7,2l-trihydroXy-4-pregrene-@20 drone and saiea-dimethyr-iminerarihydroxyl,4-pregnadiene3,2Q-diene, respectively. "In'carrying'out the process of this invention, gag-hydroxy-62ml6aldimethyl-S-preguen-ZO-one, which is prepared by the reaction of `3hydroXy-G-methyld 6-preg- 'nadien-20mila with methyl magnesium .bromide in the presence of 'cuprouschloride iis reacted with a` peracid, eg., perbenzoic"`or perha'ceti'c', preferably in `the presence fof fan alkali-metal lowerLacyiate,"efgg,potassium ors o'2 cetate, and preferably atjor below roomtempeia'- ture, 3o"jto"r30' C.; for from l'af-ew' minutes 'tov`isev`er l hours; to "produce B-hydoXy-Sdoeepoxy- "6`,ll6o-dimethylpregnan-ZO'-one.' This compoundis'gly- 'litalatedi" with Iai*lo Wer-'alkyl' diesterfk 'of'l oXalic acid, e ethyl xalate or. ethyl'oxala'te; the presence' of then dibrominated, preferably in the presence of suicieut base to absorb the hydrogen bromide produced,

elg.`,'sodium'or potassium acetateto produce the Vcorre-` sponding"21,2l-dibromo` compound. 'This compound, when reacted With an alkali-metalloWer-alkoxide in an alkfanol, eg., sodium'methoxide in 'methanol or sodium ethoxide inv ethanol, is converted'to 3hydroXy-5o,6ai epoiiyldadimethyl 17(20) pregnen Z1" oic acid lower-alkyl ester"as a mixture of "the" l7(20) cis and trans'isomers.` Reduction'of this compound with lithium allu'minum'hydride produces a mixture 'of the 17(20) ois-and" trans isomers of' 3`,3,50r,2.l-trihydroxyiog16a-di. niethyll'/,'(2 0)pregr1ene which' is then oxidized, e`.g;, with 'chromic acid, chromic anhydride, 'N-bromoacetamide 'in pyridine, after'fselective esteriiication of the 2l-hydro`xy group under mild conditions, to produce 565,21- ilihydroxy 6ccl6`a dimethyl-17(20)-pregnene3l one Zlacyla'tel: 'This compound is 'oxidatively hy d roxylated with osmium tetroxide yand an *oxidizing agent; e.g;,"'an amine oxid'per'oxid'e, an aryl iodo oxide, hydro# gon p'eroiiide, an alll'cyl peroxide lor a' peracidj to 'pro'- duce 5bt,l7,21 ltrihydroiiy- @0516er dimethylpregnane# 3,2l0di'one ZFl-acylate. v`Reaction of'this compound 7with a dehyda'ting agent;4 c g., anhydrous'hydrogenfchloride,

To a stirred mixture of 0.5 g. of cuprous chloride in A50 ml.' 'of tetra'hydrofuran `was aiidedy 50 inl. of 3' M ethereal methyl 'magnesium bromide, followed by the dropwi'se 'addition' of 51:0 g,"of3'-hydroxy-6-methyh5,16# p'regiiadie20-ohe (U.S. Patent`2,8"l7l,246 in35m1.of

at:room'tefn'prnlaturet for 3 "hours:v 1,5` ml. ofconceitrated' hydrochloric acid in .150 ml. of Water"was"then added." The' llayers were separated, the'aqueous' layer .'Wa'js vWashed thoroughly/with ethylace'tate and' the comliiied'org'anic layers werewashed with water',g dried and evaporated." The residue 'was crystallized" from ethyl y cetate'to give y2.18 g1 of -hydroxy-,laldimethyl5- regnen-20eme menager 172-175# C.l t yi f yP1.REPARA'I'I0.N 2

3,5-Hydr0xy-5a,6-Epoxy-6,1ta-Dimethylpregnaniv Lui-'tf r1.1 20,0e ffii 2 11? 7,-

Io an ice-,cold Ymixture of `l0 ml. of 40 percent pervacetic acid 1andlgf of 'anhydrous sodium acetate was slowl'yadde'd a solution of 5.0 `g.` of' 3-hydroxy6,116a dimethyl-pregnan-nZO-one in ml. of benzene; After *stirring for= 2`hours in kan ice bath," the layers were sepa- 1rated and the benzene layer was washed with water," cold 'aru'eoiis 5 4 `percent sodium hydroxide;l Water, -`dried "and evap'irated'z'ltf'reducedtfpressuiev to leave a crystalline 'residue of SB-hydrOXy-Su,jntQepoxy-,la-dimethylpregnan-ZO-one. 'Recrystallizat'ion-from acetone-gave' 3.89'fg. 'of crystals thereof melting at 1994203" C., j[.o'c]D +9 (:CHClgLfand having the'correct elemental analysis."

EXAMPLE 1 :To a solution of 3.60 g. of 3-hydroxy-5a,6aepoxy 6,6,l6tac-dimethyl-pregnan-20-one in 50 ml. of tertiary butyl alcohol was added, at 60 C. with stirring under a nitrogen atmosphere, 5.6 ml. of ethyl oxalate and 4.76 g. of 28.1 percent by weight sodium methoxide in methanol. The resulting orange colored solution was `allowed to cool to room temperature and was stirred for 2 hours. Then a solution of 1.44 ml. of ace-tic acid iand 1.66 g. of sodium acetate in 70 ml. of methanol at 10 C. was added over a period of 10 minutes. The resulting solution was cooled to C. and to it was slowly added, over a period of 15 minutes, 3.2 g. of bromine in 48 ml. o-r cold methanol, followed by 10.7 g. of 28.1 percent by weight sodium methoxide in methanol. After stirring for 1.5 hours while warming to room temperature, 16 ml. of acetic Iacid' and 3 g. of Zinc dust was added and stirring was ycontinued for 30 minutes. After filtering, 50 m1. of water was added to the ltrate and the mixture was concentrated at reduced pressure. The product was extracted with methylene chloride which was then washed with water, aqueous sodium bicarbonate, dried and then chromatographed on 150 g. of magnesium silicate (Florisil). 3.9 g. of S-hydroxy-Sa,6aepoxy6,16er-dimethyl- 17 (20)pregnen21oic acid methyl ester was eluted with hexanes (Skellysolve B) plus percent, 8 percent, 10 percent and 13 percent acetone. This compound showed infrared absorption peaks at 3638, 3480, 1718, 1648, 1380, 1235, 1202, 1164, 1105, 1061 and 1010 cm.-1

Following the procedure of Example 1, but substituting sodium ethoxide in ethanol for the sodium methoxide in methanol, there is thus produced 3-hydroxy5a,6aepoxy 6,6,16-dimethyl-17(20)pregnen21oic acid ethyl ester.

EXAMPLE 2 313,5 a ,21 -Trhydroxy- 11,1 6 a-Dimethyl-I 7 (20) -Pregnene and 21 -Acelate 2.665 g. of the chromatographed 3hydroxy5a,6a epoxy-613,16a-dimethyl-17(20)pregnen21oic acid methyl ester obtained according to the procedure of Example l, dissolved in ml. of benzene, was added to 2.5 g. of lithium aluminum hydride in ml. of tetrahydrofuran. The resulting suspension was stirred for 20 hours and then decomposed with ethyl acetate followed by water. The organic layer was separated, washed with dilute hydrochloric acid, aqueous sodium bicarbonate, dried and then evaporated to dryness. The residual 313,5,21-trihydroxy- 6,16dimethyl17(20)-pregnene was dissolved in 20 ml. of dry refluxing benzene which was then cooled to room temperature and 1 ml. of pyridine followed by 0.75 ml. of acetic anhydride were added thereto. The mixture was maintained overnight at roomv ytemperature and then diluted with cold water. The organic layer was separated, washed with dilute hydrochloric acid, aqueous sodium bicarbonate, dried and evaporated to give a residue of 3,5oa,21trihydroxy6a,l6a-dimethyl-l7(20)pregnene 21-acetate which was purified by chromatography on 200 g. of magnesium silicate. Elution was accomplished with methylene chloride plus 10 percent and 15' percent acetone. The purified product had infrared absorption peaks 3625, 1730, 1231, 1025, 952, and 820 crn.-1 in methylene chloride.

Following the procedure of Example 2, 3hydroxy5a, 6oz-epoxy-66,lu-dimethyl-17(20)-pregnen2l oic acid ethyl ester was converted to 3,5oc,21-trihydroxy-6a,16- dimethyl17(20)pregnene and the 2l-acetate thereof.

Similarly, 3,5o,21trihydroxy6a,16a-dimethyll7(20) pregnene is converted to other 21hydrocarbon carboxylic acid esters thereof by selective esteriiication of the 21- hydroxy group, eg., by reaction with the appropriate acid anhydride, acid chloride or bromide, ester by ester exchange, acid in -thepresence of an esterication catalyst, etc. Examples of 3,5a,21-trihydroxy-6a,l6er-dimethyl- 17(20)pregnene 2l-acylates prepared include those wherein the acyl group is the acyl radical of, for example, a lower-aliphatic acid, e.g., formic, propionic, butyric, isobutyric, valerie, isovaleric, trimethylacetic, 2-methylbutyric, 3-ethylbutyric, hexanoic, diethylacetic, triethylacetic, heptanoic, octanoic, a-ethylisovaleric, a cyclic acid, e.g., cyclopropylideneacetic, a cycloaliphatic acid, e.g., cyclopentylforrnic, cyclopentylacetic, cyclopentylpropicnic, cyclohexylformic, cyclohexylacetic, -cyclohexylpropionic, an aryl or alkaryl acid, eg., benzoic, 2, 3, or 4- methylbenzoic, 2,3-, 2,4-, 2,5-, 2,6-, 3,4- and 3,5-dimethylbenzoic, ethylbenzoic, 2,4,6 trimethylbenzoic, 2,4,6 -triethylbenzoic, -naphthoic, 3-methyl-a-naphtho-ic, an aralkyl acid, e.g., phenylacetic, phenylpropionic, diphenylacetic, triphenylacetic, a dibasic acid, (which can be converted to water soluble, e.g., sodium, salts) eg., succinic, glutaric, a-methylglutaric, -methylglutaric, ri-dimethylglutaric, tadipic, pimelic and suberic acid, preferably a hydrocarbon carboxylic acid containing from one to twelve carbon atoms, inclusive.

EXAMPLE 3 5 1,21 -Dhydroxya,1 6 a-Dt'methy l-1 7(20) -Pregnen-S-bne 21 -A cetate 1.188 g. of the chromatographed 3,5'a,21trihydroxy 6a,16adimethyl-17(20)-pregnene 21-ace-tate obtained according to the procedure of Example 2 was dissolved in ml. of acetone and then cooled in an ice bath. To the resulting solution was added 1.5 ml. of a solution of chromic anhydride and sulfuric acid in water [Djerassi et al., J. Org. Chem., 21, 1547 (1956)]. mixture for 15 minutes in the ice bath, water was added. The precipitated steroid was extracted With ethyl acetate which was then washed with aqueous sodium bicarbonate, dried and evaporated. The residual 5a,21dhydroxyl- 6a,16 dimethyl-17(20)pregnen 3 one 2lacetate was chromatographed on 100 g. of magnesium silicate (Florisil) and eluted with hexanes plus 5 percent to 8 percent acetone. The purilied product showed infrared absorption peaks at 3635, 1732, 1713, 1667, 1238, 1122, and 1025 cm.-1 and, after recrystallization from a mixture of ethyl acetate and hexanes, melted at -155 C.

Similarly, other 21-acylates of 3,5a,21trihydroxy 6oc,16adimethyll7(20)pregnene, eg., wherein the acyl radical of the acylate group is that of an acid named in the paragraph following Example 2, are oxidized to the corresponding 21-acylate of 5e,21-dihydroxy6a,16adi methyl-17 (20 -pregnen-B-one.

ExAMiLn 4 5 0:,1 7a,21 -Trihydroxy- 11,1 6 oL-Dz'm ethylpregnane-3,20

diane 21 -Acetate 661 mg. of the chromatographed 5a,21-dihydroxy 6a,16oL-dimethyl17(20)pregnen 3 one 21 acetate obtained according to the procedure of Example 3 was dissolved in 50 ml. of tertiary butyl alcohol containing 0.75 ml. of pyridine and to the solution was added at room temperature 2.0 m1. of a 2.06 M solution of N- methylmorpholine oxide peroxide in tertiary butyl alcohol followed by 10 mg. of osmiurn tetroxde. The solution was stirred overnight and then a small amount of filter aid was added followed by 15 ml. of a solution made by dissolving 675 mg. of sodium hydrosulfite in 100 ml. of water. The mixture was stirred for one-half hour, filtered, Vthe filtrate concentrated to a small volume by evaporation and then extracted with methylene chloride. acid, aqueous sodium bicarbonate, dried and evaporated. The residue was chromatographed on 100 g. of magnesium silicate. 5a,17a,2l-trihydroxy-a,16a-dimethylpregnane-3,20dione 21-acetatev was eluted with hexanes plus about 12 percent acetone and gaveV infrared absorption After stirring the The extracts were washed with dilute hydrochloric peaks at 3710, 3630, 3535, 1750, 1728, 1713, 1234, 112:6, 1056, 9,818', and 838 cm-l in methylene chloride. A sam' ple thereof melting at 180-1 82 C. was obtained by c'rysf tallization from a mixture of hexanes and ethyl acetate. Similarly,` other '2l-acylates of 5a',21-dihydroxy-,6u, 16dimethyl-17(20)pregnen3one, e.g., wherein the acyl radical of the acylate group is that of an acidl named in the paragraph following Example, 2, are oxidatively hydroxylated toy the corresponding 21-acylate of 5a,17a,21 trihydroxy-6oc,1a-dimethylpregnane-3,20dionef EXAMPLE 267 mg. of the chromatographed 5a,17a,21trihydroxy 6a,lGot-dimethylpregnane-S,ZU-dione 21acetate obtained according to the procedure ofExarnple 4 was dissolved in 80 ml. of chloroform to which 1 m1. of ethanol was then added and the solution cooled in an ice-salt bath. Anhydrous hydrogen chloride was bubbled through the cold solution for 4 hours. Then nitrogen Was bubbled through for 15 minutes and the solution was washed with aqueous sodium bicarbonate, water, dried and then evaporated. The residue was chromatographed on 75 g. of magnesium silicate. Only one peak was eluted and a total of 235 mg. of mostly crystalline material came off the column with hexanes plus about 8 percent acetone and was recrystallized from a mixture of hexanes and ethyl acetate to give 191 mg. of 6ot,16adirnethyll7a,21 dihydroxy-4-pregnene-3,20-dione 21acetate melting at 174-175 C. and having infrared absorption peaks in mineral oil mull at 3515, 1753, 1722, 1650, 1603, and 1240 cnn-1.

Similarly, other 21-acylates of 5a,17a,21trihydroxy 6a,16a-dimethylpregnane-3,ZO-dione, e.g., wherein the acyl radical of the acylate group is that of an acid named in the paragraph following Example 2, are dehydrated to the corresponding 21acylate of 6a,l6adimethyl 17oc,2l-dihydroxy-4-pregnene-3,20-dione.

EXAMPLE 6 6 a,1 6 a-Dmethyl-I 7a,21 -D ihydroxy-I ,4-Pregnadene- 3,20-d0ne 21 -Acetate A solution containing 200 mg. of 6oc,l6udimethyl 170:,21-dihydroxy-l-pregnene-S,ZO-dione 2l-acetate, 0.2 g. of selenium dioxide, ml. of tertiary butyl alcohol and 0.5 ml. of acetic'acid was heated at reflux for a period of 8 hours. Most of the solvent was then evaporated under a stream of nitrogen. Methylene chloride was added and the solution was filtered through a bed of diatomacieous earth. The filtrate was washed consecutively with water, freshly prepared aqueous ammonium sulde solution, dilute aqueous ammonium hydroxide solution and water. The solution was dried over magnesiurn sulfate and the solvent was removed by evaporation under a stream of nitrogen. The residue was dissolved in methylene chloride and chromatographed through a 10 g. magnesium silicate column packed wet with hexanes. The column was developed with hexanes containing increasing amounts of acetone to give nalwdimethyl-l7a,2l-dihydroxy-l,4-pregnadiene-3,20 dione 21-acetate.

Similarly, other 2l-acylates of 6,16adimethyll7a,21 dihydroxy-4-pregnene-3,ZO-dione, e.g., wherein the acyl radical of the acylate group is that of an acid named in the paragraph following Example 2, are converted to the corresponding 2lacylate of 6a,l6adimethyll7a,21 dihydroxy-l,4pregnadiene3,20-dione.

EXAMPLE 7 diane A solution was prepared containing 0.5 g. of 6,16a dimethyl-170:,21-dihydroxy-4-pregnene-3,2O-diene 21-aceter, dried over anhydrous sodium sulfate and evaporated to give 6ot,16dimethyll7a,21-dihydroxy-4-pregnene- 3,20-dione, M.P.195-200 C.`

Similarly, 6a,16oz-dimethyl-170:,2l-dihydroxy-1,4preg nadiene3,20dione 21-acetateis hydrolyzed with potassium bicarbonate to 6a,16a-dimethyl-17a-21-dihydroxyl,4-pregnadiene-3,20-dione.

We claim: l. Compounds represented by the formula:

C OO-lower-alkyl CH Y CH3 l -C Ha l H0 i o om 3. Compounds represented by the formula:

-CHs

l i t Ho CH3 wherein R is selected from the group consisting of hydrogen and the acyl radical of a hydrocarbon carboxylic acid containing from 1 to l2 carbon atoms, inclusive.

6. Compounds represented by the formula:

CHa

i e HO CHS wherein Ac is the acyl radical of a hydrocarbon carboxylic acid contaniing from 1 to l2y carbon atoms, inelusive.

8. Compounds represented by the formula:

References Cited in the file of this patent UNITED STATES PATENTS 2,868,808 Babcock Ian. 13, 1959 2,940,968 Sletznger et a1. June 14, 1960 OTHER REFERENCES Rngold et al.: J. Am. Chem. Soc., v01. 81, pages 3712-16 (July 20, 1959).

JAN 

1. COMPOUNDS REPRESENTED BY THE FORMULA: 